World Fish Migration Day 2016

The 2016 World Fish Migration Day awareness theme “connecting fish, rivers and people” on May 21st provides the opportunity for Oxfam to reflect on the importance of open rivers for fish migration throughout the Mekong River. Oxfam is continuing to develop the sustainable and environmentally friendly relationship between the local population, fish species and the world’s twelfth longest river which is as a prime example of human reliance on a fresh water ecosystem and migratory fish.

Over 48 million people in the Lower Mekong River are dependent on the availability of migratory fish species (World Fish Migration Foundation, 2016) but the Mekong is fast becoming home to extensive hydropower activities. Man-made structures are modifying the ecosystem at a high cost to the environment and limiting the free flow necessary for migratory fish to reach critical habitats for reproduction and feeding. Oxfam in Cambodia took the occasion of WFMD2016 to interview Dr Eric Baran, a Senior Scientist at non-profit research organisation WorldFish Cambodia who has over fifteen years experience researching Mekong fish and fisheries, about the change in fish migratory patterns and the cost of infrastructure development to the environment and Mekong River population.

Question and Answer

Why is it important to recognise World Fish Migration Day 2016?

The existence and intensity of fish migrations in rivers are a reflection of the health and ecological status of these rivers, and healthy rivers are essential to human life. When fish migrations become minimal or impossible, this is a sign that the river and the environment on its banks are becoming too bad for life. For instance they are getting polluted, blocked by many dams, or too shallow due to water abstraction.

Along the Mekong River

About 40 per cent of the Mekong fish yield is made of migratory fishes. This represents about 800,000 tonnes of migratory fishes harvested and consumed each year. Eight hundred thousand tonnes of freshwater fish represent twice the whole marine fishing sector in Canada, France or New Zealand.

Why is fish migration essential for a healthy river?

A river is more than just water; it can be seen as a living system, made of water, but also of aquatic organisms, sediment, nutrients, habitats and of floods. The functioning of that living system needs to be sustainable, meaning more or less natural and regular year after year, decade after decade. This is what we call the river health.

Fish migrations are not essential to the river, but they are a warning signal about the health of the river: when migration becomes impossible, it means that the river is not in good health any more. Ultimately, a river can die; then it becomes like a polluted canal, with no life in the water and no life on its banks either.

How does fish migration affect the livelihoods of those living along the Mekong and primary food supplies of indigenous and poor communities?

Cambodia holds two world records, and is number one in terms of quantity of fish caught per person and per year, and of kilograms of river fish eaten per person, per year. The fish catch in Cambodia, 2014, was 600,000 tonnes, including 500,000 tonnes of freshwater fish which is as much as the whole marine fishing sector in UK and four times more than that of Australia.

Migratory fish in the Mekong are a huge resource for the communities living by the water bodies and most fisheries are organized to catch these fishes as they migrate. A study by the Cambodian Fisheries Administration two years ago showed that fish are the number two food item in the country, after rice. Each year, each Cambodian eats in average 40 kg of river fish, 4 kg of freshwater aquatic animals (mollusks, frogs, etc), 17 kg of marine fish and 1 kg of aquaculture fish. Fish provide 37 per cent of the total protein intake and 28 per cent of the fat intake.

What does the increase in hydropower dam development and manmade infrastructure mean for the fish and in turn, those who rely on their migration through the Mekong?

Rapid and unplanned dam development is the number one threat for fish migrations and therefore for food security in the region, in particular in Cambodia and Laos.

In 2000 there were 16 dams in the Mekong, nowadays there are about 45 dams and by 2030, there are plans for about 88 dams in total. These dams produce much needed electricity, but they also block rivers, and therefore block fish migrations throughout the basin. The consequence is that migratory fish will not be able to move from their breeding grounds to their feeding grounds any more, and might disappear.

A study commissioned by the Mekong River Commission in 2010 showed that if 11 dams are built along the Mekong mainstream as planned, then a loss of at least 600,000 tonnes of migratory fish can be expected each year. This represents as much as all the fish produced by all 15 countries of West Africa or twice the total annual livestock production in Cambodia and Laos together.

How can a healthy aquaculture* system reduce poverty and hunger?

Intensive aquaculture can produce a lot of fish and complements the capture fisheries** sector, but will not replace it before several decades, and before it is severely degraded.

In the Mekong region, aquaculture fish production represents as much as capture fish, with 2.3 million tonnes from capture fisheries and about 2.1 million tonnes from aquaculture production in 2012. However, about 80 per cent of that aquaculture is produced in Vietnam and the aquaculture sector is not very developed in the three other countries of the Mekong. In Cambodia for instance each person eats in average, each year, 58 kg of wild fish, and only 1 kg of aquaculture fish.

In Cambodia, Laos and Thailand, it is good to see the aquaculture sector developing fast, but that sector is far from being able to compensate in the near future for the loss of capture fish. Furthermore, the aquaculture sector tends to produce high value fish for export or sale to wealthy customers, rather than cheap fish accessible to the poor. In that context, in the coming ten to fifteen years there should be a strong emphasis on protecting natural capture fisheries, complemented with a development of the aquaculture sector.

*Aquaculture: Farming (i.e. breeding and/or feeding) of aquatic animals or plants in a controlled environment

**Capture fisheries: Catching of wild fish at sea and in rivers or lakes

How can fisheries and aquaculture be used as a platform to improve gender equality?

Fisheries are already a sector that empowers women, because in Southeast Asia men tend to catch the fish, but women tend to process and sell that fish, which allows them to make profit and gives them economic power. A better development of processing and improved trade chains would also increase the profit from the catch, which would in turn favour women.

How has your research impacted policy and poverty?

At WorldFish in the Mekong we conduct research and try to act at three levels:

1) Improving natural fish production in the natural environment, for instance by creating protected areas near rice fields, so that the production of rice field fish is increased.

2) Informing governments about the negative impacts of building dams that have not been carefully planned, and by prosing option to mitigate the negative consequences of dams on fish

3) Developing aquaculture, in particular techniques and fishes accessible to the poor

Which fish breeds use the Lower Mekong River on their migratory path?

The Mekong River features at least 165 migratory species that undertake either long or short distance migrations. Among them, at least 103 species undertake long distance migrations over hundreds of kilometres, for instance from downstream floodplains in Cambodia (where many species feed) to upstream rivers in Laos or Thailand (where many species breed). The biggest migratory fish is the giant Mekong catfish; it can reach 300 kg and migrate over 1000 km. Many migratory species are small, such as the Siamese mud carp and yet they swim several kilometres per day.

Further information available at:

Fish and nutrition in Cambodia

Fish resources in Cambodia

Mekong dams, fish and sediment